The Short Empire flying boats met needs of the British Air
Ministry for a long-ranged four-engined flying boat, and of the major
contemporary airlines for an aircraft suitable to serve a link between
Britain and Australia. The results were the S.23, officially the
'C-Class', but known to Shorts as the Imperial Flying Boat; and the S.25,
which became famous in WW.2 service as the Sunderland.

The Imperial Flying Boats became known by the less cumbersome 'Empire'
title, and were christened with names beginning with 'C'. The first
aircraft completed was G-ADHL 'Canopus', in June 1936, launched on
2 July. The type entered service that October.

Initial orders from Imperial and Qantas led to construction of 42
aircraft. 31 of these were the S.23 version, nine were the S.30 (815
hp/610 kW Bristol Perseus XIIc) and two were S.33s, also ultimately
powered by the Perseus XII. The S.33s were the end of the series, launched
in April 1940.

Empire flying boats not only served the England-Australia route, but also
flew a trans-Atlantic service via Ireland and Newfoundland, using G-ADHM
'Caledonia' and G-ADUV 'Cambria', with increased fuel
capacities and reduced payloads. In August 1939 a weekly service from
Southampton to New York was begun, with the flying boats G-AFCU 'Cabot'
and G-AFCV 'Caribou' relying on air-to-air refuelling from Handley
Page Harrow bombers converted to tankers, and stationed in Ireland (G-AFRL)
and Newfoundland (G-AFRG and G-AFRH). The service terminated at the end of
September 1939.

Australia showed reluctance on a number of grounds to accept the costly to
run Empire boats. Nonetheless, they could outperform the DC-2s on the
Australian end of the Qantas-Imperial route, and finally, Qantas' first
'Empire' service took off from Sydney's Rose Bay on 5 July, 1938, flown by
VH-ABF 'Cooee'. The inaugural Empire Airmail flight, flown by G-AEUB
'Camilla', followed on August 4.

World War 2 meant that the existing air route from England to Australia
had to be diverted, to become the Horseshoe Route from Sydney to
Durban via Cairo. Qantas, initially responsible for the Sydney-Singapore
section of the service, extended its portion to Karachi, where BOAC
(formerly Empire) took over. At the end of 1941, with Singapore under
attack, the route terminated. It was reopened when, later, Japan lost
Burma and Malaya. Qantas operated a number of the Empire boats under
Australian registration, as well as several owned by Imperial / BOAC. With
the outbreak of war, three of their aircraft were in India and three of
the BOAC flying boats were in Australia, so ownership was exchanged.

The RAAF used five examples, numbered A18-10 to A18-14. Two initially went
to 11 Sqn. - G-ADUT 'Centaurus' and G-AEUA 'Calypso', which
became A18-10 and -11. In June 1940 VH-ABC 'Coogee' and VH-ABB 'Coolangatta'
followed on contract with Qantas. Finally, the S.33 VH-ACD 'Clifton'
joined them in March 1942. They performed coastal patrol and transport
duties with 11, 13, 20, 33 and 41 Sqns. Only 'Clifton' and 'Coolangatta'
returned to civil service, the others being lost in accidents or, in the
case of 'Centaurus', in a Japanese air raid on Broome, WA, on 3
March 1942. G-AEUC 'Corinna' was also destroyed at moorings in
Broome the same day.

VH-ABD 'Corio' went to Imperial as G-AEUH and was shot down near
Koepang on 30 January 1942, and G-AETZ 'Circe', another British
aircraft sometimes operated by Qantas, was believed to have been lost due
to enemy action on 28th February, 1942, between Tjilitjap and Broome.

With their dramatic wartime careers, it was appropriate that the first
Qantas aircraft to enter the liberated Singapore was VH-ABG
'Coriolanus', on 8 October 1945. Post-war, the same aircraft
inaugurated the Sydney / Brisbane / Noumea / Fiji route on 19 November,
flying it until December 1947. 'Coriolanus' was the last Empire
flying boat in operation in the world. It was broken up in Rose Bay during
1948.